Respirators commonly include a face piece molded from a soft, pliable rubber-like material, the face piece supporting members for attaching one or more air-purifying cartridges to the face piece, and for attaching an exhalation valve, the said members being accommodated in apertures through the face piece.
In order to secure the face piece over the user's nasal and oral areas, straps are attached to rearward portions of the mask, the straps usually being of an elastic material for them to be passed over or around the user's head, and then adjusted for them to draw the mask into sealing relationship with the nasal and oral areas of the user's face in a continuous line or zone extending around the user's nose and mouth.